A modern programming language that makes developers happier.

kotlinlang

What’re the main differences between Kotlin and Scala? I mean, I started using Kotlin this weekend and feel many similarities for an intermediate programmer between both languages. 

as someone who's learning Scala, on the surface there are a lot of similarities in syntax

but Kotlin aims to be more pragmatic and easier to learn and use. also aims for good Java interop

and there were a lot of...interesting...decisions made in the Scala language, like creating their own collections framework, or implicit type conversions, or IIRC the way generics are implemented

What features Kotlin has, and Scala doesn’t? 

&gt;  the way generics are implemented
what did Scala do with generics?

I'm not sure what Max is referring to there; they use similar declaration-side variance as Kotlin. syntax is oddly `[+T]`/`[-T]`/`[T]` instead of `&lt;out T&gt;`/`&lt;in T&gt;`/`&lt;T&gt;` though

IMO the main difference is that Kotlin avoids many of the more questionable design choices of Scala

what does Scala's `_` mean? long list of rules. what does Kotlin's `it` mean? simple.

and yeah, Kotlin is pragmatic. Scala has some features like non-local returns and structural typing that are simply expensive to implement on the JVM, and Kotlin just doesn't have them.

I just remember reading the Scala book and there being _a lot_ of sections about the type system (half the book? more?) and never actually understanding generics

well, Scala does have a lot of type-related machinery, with more manipulation being possible at compile-time (such as mixin traits) and runtime (such as reified generics backed by implicit values), but I wouldn't call those part of generics exactly

I'm probably misremembering :sweat_smile: it was a few years ago.

but yeah, relearning Scala and things like ++: and +: for various collection manipulations, plus how you can say `new Instance() with Interface1 with Interface2` is...on that list of interesting choices

(to be fair, `object : Instance(), Interface1, Interface2 {}` is legal in Kotlin, but there are certain patterns that can't be expressed. aside from some inherent awkwardness, Scala has a self type and Kotlin doesn't, which makes a difference for some of those uses)

I didn’t use Generics yet, but I studied and felt a bit complex. I think it is essential to know to program more deeply. 
I’m not a developer but a Ph.D. student and a data scientist. I use Python and have been studying Scala and Spark.  

So, significant differences are related to advanced things